Cholinergic drugs CIS

Question 1

A 29 y/o male presents unconscious with nonreactive, pinpoint sized pupils, massive oral foaming, and muscle fasciculations. His pants are wet with urine.

1) What receptor family is most likely involved in his presenting symptoms?
2) An agent from which drug class was most likely ingested?
3) What drug, or combination of drugs, is most likely administered as an antidote?

Answer 1

1) Cholinergic
2) AChE inhibitor
3) Atropine and pralidoxime

Question 2

A 46 y/o female presents complaining of dry eyes and a dry mouth. Her symptoms have been present for the past 6 months and have progressively worsened. She saw an ophthalmologist 3 months ago and has been using artificial tears with little relief. She often has to wake up in the night to drink water and frequently has to drink to help swallow her food. She experiences the feeling of grit or sand in her eyes on a daily basis.

1) What drug mechanism of action is most appropriate in this situation to treat the patient’s presenting symptoms?
2) What drug is most appropriate in this situation?
3) If the correct drug is prescribed, what adverse effect(s) could the patient expect?

Answer 2

1) mAChR agonist
2) Pilocarpine or cevimeline
3) Diaphoresis, diarrhea, rhinorrhea, urination

Question 3

A 2 y/o female presents to the ED after an accidental overdose of antihistamines. Her temperature is 102.5° F and pupils are fixed and dilated. Heart rate is 160 bpm (normal 120 bpm). She shows signs of delirium and is noted to have marked cutaneous vasodilation upon physical exam.

1) She is exhibiting symptoms of overactivity of which division of the nervous system?
2) Which GI/GU symptom would you expect this patient to exhibit?
3) Stimulation of which receptor will most likely correct her combination of symptoms?
4) Which agent is most appropriate?

Answer 3

1) Sympathetic
2) Urinary retention
3) mAChRs
4) Any uncharged AChE inhibitor is appropriate (physostigmine, rivastigmine, galantamine)

Question 4

An 83 y/o female resident of a nursing facility presents with a 2 month history of worsening urinary incontinence. Three years ago she presented with the same symptoms, which were adequately managed with adult diapers and bladder training at the time.

1) She is exhibiting symptoms consistent with the activation of which division of the nervous system?
2) Which agent(s) will alleviate her symptoms?
3) What is the MOA?
4) What adverse effects would you counsel the patient to expect?

Answer 4

1) Parasympathetic
2) mAChR antagonist
3) Oxybutynin (prototype) or darifenacin and solifenacin (fewer side effects)
4) Xerostomia and constipation

Question 5

A 52 y/o male smoker presents with chronic obstructive pulmonary disorder (COPD).

1) Which receptor should be targeted by pharmacologic therapy?
2) Which agent is appropriate in this situation?
3) What adverse effect(s) do you expect?

Answer 5

1) mAChR antagonists
2) Tiotropium or ipratropium
3) Decrease in mucus production which could lead to upper respiratory tract infection

Question 6

A 61 y/o male presents to an ophthalmologist complaining of double vision and droopy eyelids. He first noticed this double vision about 1 year ago and says it has been gradually worsening. He says it also gets worse during the day. Later in the day he notices progressive difficulty with chewing and he has to stop eating. The jaw fatigue doesn’t go away until after 1 to 2 hours rest. On physical exam, there is fatigable ptosis without increased skin tissue. He is diagnosed with myasthenia gravis.

1) Which drug is most appropriate to treat this patient’s symptoms?
2) What and adverse effect(s) to GI/GU and eyes are expected?
3) How does glycopyrrolate and hyoscyamine control these adverse effects?

Answer 6

1) Acetylcholinesterase inhibitors
2) Increased urination, loose stools, watery eyes
3) Anticholinergic drugs that have little or no effect on nAChRs